proFTPd + Mysql + shared folders + apache + tomcat

I have followed the tutorial for setting up ProFTPd with mysql backend. Everything is working fine.
What I want to do is to configure the following:
user1, user2, user3, user4
user1, user2, user4 are in groupA
user2, user3, user1 are in groupB
user1, user3, user4 are in groupC
user2, user3, user4 are in groupD

I want groupA to be able to upload to /var/www/ApplicationA
I want groupB to be able to upload to /var/lib/tomcat6/webapps/ApplicationB
I want groupC to be able to upload to /storage/ApplicationC
I want groupD to be able to upload to /var/www/ApplicationB

The point is actually simple... I want my users to be able to upload to their own homepages, but also to share some spaces with others, one of those spaces being httpd or tomcat directories